1. Field of the Invention
The present invention relates to a CD-ROM for displaying characters and drawing with a laser beam by synchronizing sound (or voice) and laser-beam-drawn image information to each other, and to a CD-ROM reproducing system suitable for use with the CD-ROM.
2. Detailed Description of Related Art
A laser display is well known in the art. According to the display, moving image or still image(s) is a laser beam(s) is projected on a screen such as a wall, a cloud, smoke, water, snow surface, etc., for displaying thereon a moving image(s) by scanning the laser beam in the directions of x-axis and/or y-axis using a galvanometer, and, at the same time, sound (or voice) information such as music is generated as effect sound in synchronism to the image formation.
Heretofore, however, data for scanning by the galvanometer are stored in a recording medium such as a floppy disk, a IC cards or a hard disk. Such recording medium is inadequate for direction taking long time in view of continuous reproduction and storage capacity. In addition, sound (or voice) information recording mediums are used separately from image information recording mediums such, for example, as record disks or magnetic tapes. Therefore, reproducing systems for the sound information and the image information are separately constructed each other, and it has been difficult to synchronize these systems to each other. Accordingly, it has been extremely difficult to obtain substantially perfect synchronization such that synchronization of image formation by the laser beam with sound information is not felt unnatural to the audience.
In order to solve the above problems inherent in the prior art, various researches and experiments has been repeatedly conducted by the inventor of this invention. As a result of this, following conduction is obtained. Considering the presently popular CD-DA (compact disk digital audio), it is possible to attain long continuous playing by using CD as recording medium for a laser display system. Also, it is possible to substantially perfectly synchronize the sound information and the formation of image by laser beam by simultaneously recording the sound information and the galvanometer scanning information in one and the same CD.